Brown disperse 4-carboxamido-4&#39;-phenylazoazobenzene dyes

ABSTRACT

Yellow-brown to red-brown disperse disazo dyes, useful for dyeing water swellable cellulosic or synthetic fibers or blends or mixtures thereof to light-, sublimation-, crocking-, wash- and drycleaning fast shades, which dyes have the formula X-N N-Y-N NZ-NHCOR wherein X is phenyl, optionally containing 1-3 substituents, Y and Z each is 1,4-phenylene, optionally containing 1-2 substituents, or 1,4-naphthylene, and R is alkyl, alkoxyalkyl, cyclohexyl, benzyl, phenyl or phenyl monosubstituted with methyl, methoxy, Cl, Br or NO2.

United States Patent Blackwell et al. Sept. 9, 1975 BROWN DISPERSE 3,359,255 l2/l967 Liechti 260/187 4 CARBOXAM[DO 4I 3,45l 99l 6/1969 Kleiner 260/187 PHENYLAZOAZOBENZENE DYES FOREIGN PATENTS OR APPLICATIONS [75] Inventors: John Blackwell, Kennett Square, 378.440 7/1964 Switzerland 260/187 P Richard Edwin Pea 4,] 10342 6/1966 Japan 260/[87 Wilmington, Del. [73] Assignee: E. I. Du Pont de Nemours and prutnary bxamuiler Henry p y wilmingmn De] AS81810"! Examiner-Robert W. Ramsuer PP N01 2751033 Yellow-brown to red-brown disperse disazo dyes, useful for dyeing water swellable cellulosic or synthetic [52] U S Cl I V V k 260/137. 8/21 8/4 fibers or blends or mixtures thereof to light-, sublima- 2t5U/l74' 260/178' 2 60/I84- 260/l8 tin-, crocking-, washand drycleaning fast shades, I] [m Cl 2 4 H 6 31/04 which dyes have the formula XN=A (58] Field of Search 260/187, 177, 185, 184 IYJY N=NTZNHCOR Y X phenyl tnally containing 1-3 substltuents, Y and Z each 1,4-phenylene, optionally containing l2 substituents [56] References Cited or L4-naphthylene, and R is alkyl, alkoxyalkyl, cyclo- UNITED STATES PATENTS hexyl, benzyl, phenyl or phenyl monosubstituted with 2,127986 8/[938 Rnos 260/]87 methyl, methoxy, Cl. Br Gr N02. 2.135964 11/1938 Dahlen ct a]. 260/185 2563,09! 8/!951 Wright H 260/187 2 Claims, No Drawings BROWN DISPERSE 4-(ARBOX MlDU-4'-PHENYLAZ()AZOBENZE E [)YES BACKGROUND OF THE INVENTION 1. Field of the lnvcntion This invention relates to water insoluble brown disaYo dyes which have utility in the dyeing of a broad spectrum of synthetic and natural materials. especially water swcllable cellulosic materials. or mixtures or blends of such synthetic and natural materials.

2. Description of the Prior Art It is well known in the art that synthetic fibers, for example. fibers prepared from polyesters. polyamides or cellulose acetate. can be dyed with a wide variety of disperse dyes whose solubilitics in water vary from very low to moderately high.

Natural fibers such as water swellable cellulosic lihcrs. especially cotton. are dyed by processes. and with dyes. which usually differ markedly from the processes and dyes employ ed with synthetic fibers. The conventional methods for dyeing water swellable cellulosic materials may be summarized as follows:

I A high molecular weight water insoluble dye is formed within the material. either by reacting two smaller components. as in the formation of an azoic dye by a coupling reaction. or by a chemical reaction which renders insoluble a soluble dye precursor. as in \at and mordant dyeing.

. A water soluble preformed dye having an affinity for the cellulosic material is exhausted onto the material from an aqueous solution by a procedure which involves reducing the solubility of the dye in the aqueous solution. as with direct dyes.

3. A dye containing a substituent which reacts with the cellulose or a modified cellulose is exhausted onto the material from either an aqueous or non aqueous solution under conditions such that the dye is chemically bonded to the substrate. as with fiber reactive dyes.

4. Water insoluble pigments are bonded to the cellu lose with polymeric materials. as in pigment print A finely divided form of a water insoluble dye is incorporated into the cellulose during a manufac* turing step. as is sometimes done during spinning of viscose rayon.

None of these conventional procedures can be used to dye water swellahle cellulose by directly introducing into the material a preformed. nonreactive. water insoluble dye since such dyes have little natural affinity for or substantivity to such cellulosic materials.

Representative of the aforesaid processes wherein dyes are formed in situ after a precursor is deposited on or within the cellulose arc processes disclosed in US. Pat. Nos. 396.692 and 2.069.2[5 and British Pat. No. LIV/L074. A process employing water soluble preformed dyes for dyeing cellulose is discussed in the Journal of the Society of Dyers and ('olourists. 73. 23 l 1957 I.

The aforesaid processes suffer from a variety of disadvantages. such as complexity of application. inability to achieve a broad spectrum ofcolors. and low fastncss of the dyed cellulose to aqueous washing and/or dry cleaning with organic solvents.

The use ot'dyes of low water solubility for dyeing cotton is disclosed in British Pat. No. l.l i127). The pro- (ill cess involves the application of dye. water and urea or a structurally related compound to the substrate. followed by heating. In such a process dye utilization frequently is poor and undesirable basic degradation products from the urea or related compound may be formed.

Problems in addition to the above are encountered in the use of prior art dyes and dyeing processes for blends or mixtures of water swcllable cellulosic and synthetic materials. Because of basic differences in the chemical and physical properties of the two types of materials. the components of the blend or mixture usually are dyed in complex two-stage processes employing two different types of dyes. each component being dyed independently of the other in a separate step. Cross-staining may result and the amounts of dyes re quired usually are high. with each component undesir ably interfering with the dyeing of the other. When cross-staining occurs. the dye must be capable of being scoured off the stained component. Even under opti mum conditions. balance. that is. equal shade and shade strength. between the components of the blend is difficult to achieve. If the dyed fabric lacks balance. under use conditions frosting (discolored areas) will occur in the regions of maximum wear. The complexi ties ofthe aforesaid two-stage process for dyeing blends also can be appreciated from a consideration of the divcrgency of operating conditions between conventional dyeing processes for cellulosic and for synthetic materials. In contrast to the prior art procedures for dyeing water swellahle cellulose. the usual procedures for dycing synthetic materials are based on dissolution of water insoluble dyes in the synthetic material.

Representative of prior art on the dyeing of blends of cellulosic and synthetic materials employing a two stage process is US. Pat. No, 3.3[3590 Analogous to the dyeing of such blends and confirming the aforesaid distinction between water swellable cellulosic materials and nonswellable cellulose acetate. US. Pat. No. 3153.563 discloses a twostage process wherein the cellulose acetate is dyed with a water insoluble dye without coloring the cellulose which then is dyed in an independent step.

ln order to avoid the aforesaid problems relative to the dyeing of blends or mixtures of water swellable cellulosic and synthetic materials. prior art printing operations frequently are carried out using resin bonded pig ments. Since such processes provide only surface coloration. the prints obtained often exhibit crocking, poor hand" and low fastness to washing and dry cleaning.

The swelling of cotton fibers and other similar cellulosic materials by water has long been known. Swelling usually is rapid upon contact with water. but it is facilitated by wetting agents and by heat. The swollen materials are enlarged. more flexible. reduced in strength. and otherwise modified in physical and mechanical properties. Because of their open structure. swollen cellulosic materials can be penetrated by and reacted with low molecular weight water soluble compounds. Valko and Limdi in the Tcytilc Research Journal. 32. 331 337 1 1962) report that cotton can be swollen with water containing both high boiling. water soluble, nonreactive compounds of limited molecular weight and a cross-linking agent. The water can be removed with retention of swelling and crosslinking can then be effected. The authors suggest that the technique may be useful not only for the introduction into cotton of water soluble reactive materials (erosslinking agents) but also other reactive materials which are insoluble in water but soluble in said high boiling. water soluble. nonreactive compound. A similar technique is described in US. Pat. No. 2.339.913 issued Jan. 25. I944 to Hanford and Holmes. The cellulosic is swollen with water. the water then is replaced with methanol-benzene and fi nally with benzene. with retention of swelling. A cellulose-reactive material (crosslinking agent) is added as a benzene solution and crosslinl iing is effected.

Blackwell. Gumprccht and Starn in Canadian Pat. No. 833.343 disclose a process for dyeing water swellable cellulosic materials with disperse dyes. which process comprises contacting a water swell-able cellulosic material in any sequence with the following:

I. water in an amount sufl'lcient to swell the cellulose;

2. a dye in an amount sufficient to color the cellulose. a boiling saturated solution of which dye in ().l Molar aqueous sodium carbonate exhibits an optical absorbance not in excess of about 30: and a solvent in an amount sufficient to maintain swelling of the cellulose if water is removed. and which a. is at least 2.5 weight "/1 soluble in water at 25C.. b. boils above about 150C. at atmospheric pressure. c. is a solyent for the dye at some temperature in the range of about (1 to 225C., and d. has the formula 1M1 I M an.

wherein n is (J or 1;

m is a positive whole number; R is H. C alkyl. aralkyl or alkaryl.

NH(phenyl l. or NH( naphthyl R is C alky l. C cyeloalkyl. C aralkyl or alkaryl. (I; aryl. C aryl. or furfuryl;

lCH) .(H in which r is 2. 3. or 4.

1 is (l. l. 2. 3 or 4 but no greater then y. and R is as above-defined; 5 provided that at some stage during the process the interior of the swollen cellulose is contacted with a solution of the dye in aqueous solvent or solvent.

Particular embodiments of the aforesaid process include those wherein said solution is formed within and- /or outside the swollen cellulose and those wherein so lution of dye in aqueous dye solvent or dye solvent is achieved by means of heat. by reducing the proportion of water to dye solvent. or by adding an auxiliary solvent. Embodimcnts of the process also include dyeing at elevated temperatures.

Still other embodiments of the aforesaid process include the dyeing of blends or mixtures of cellulosic and synthetic materials. such as polyamide or polyester. with the same dye. In such a process the cellulose is dyed as described above and the synthetic material is dyed either at the same time or in an independent step of the process.

OBJECTS AND SUMMARY OF THE INVENTION It is an object of this invention to provide yellowbrown to red-brown disperse disazo dyes which are useful in the above-described process of Blackwell et al. for dyeing water swell-able cellulosic materials and blends or mixtures thereof with synthetic materials lt is a further object to provide dyes which give a good balance of shade when used to dye the aforesaid blends or mixtures. Another object is to provide disperse dyes which inhibit good to excellent fastncss to light. washing. crocking. sublimation and drycleaning when applied to water swellable cellulosic materials, synthetic materials or blends or mixtures of such cellulosie and synthetic materials.

In summary. the present invention resides in dyes of the formula N=N N=N -NHCOR wherein X is H. alkyl. Cl, Br. CN. CF,,. (.Oalkyl. COphenyl. SO- alkyl. SO phenyl. CONHalkyl. CON(alkyl) CONHphenyl. CON( alkyl )phenyl. SO N( alkyl sO Nlalkyl )phenyl. NHCOalkyl. NHCOphenyl. (O- alkyl or CO phenyl,

x is n. tinttllkOXy. Cl. Br or CN.

X is H. alkyl. alkoxy, Cl. Br or N0 Y is H. methyl. ethyl. methoxy. ethoxy or Cl and Y: is H. methyl. ethyl. methoxy or ethoxy. or Y, and

(1H Y. together with the benzene ring complete a IA- naphthylene radical.

Z is H. methyl. C1 or NHCOR and Z is H. methyl or methoxy in the para position to Z,. or Z and Z together with the benzene ring all l.4-naphthylene.

65 and R is alkyl. alkoxyalkyl. cyclohcxyl. benzyl. phenyl or phenyl substituted once with methyl, methoxy. Cl, Br or N0 each of said alkyl, all-toxy and alkoxyalkyl in X,. X X and R containing li\ carbon atoms.

DETAILED DESCRIPTION OF THE INVENTION The brown disperse disazo dyes of the formula set forth above are prepared by a series of reactions which involve diazotizing a primary aromatic amine of the formula wherein X,, X and X;, are as defined above, coupling the resulting diazo compound to a second primary aromatic amine of the formula wherein Y and Y. are as defined above and coupling the resulting monoazo compound to a third primary aromatic amine of the formula aniline N-oct lanlhranilamide O-Jtlor P-toluidine leaprylamidrianiline p-hnl lanilinc Z-cthy lsulfon laniline p-hutotyanilinc o-phcnetidinc o .nior Pchloroaniline om or p hromoanilinc Z-chlorii-4-loluidilic I.5dichloroanilinc 3-chloro2-triluidinc 2v -dihro|noanilinc chl in -4-c\anoanilinc 5-chloro-I-cyanoanilinc \"JN- or p-anisidinc Z-chloro-S-dibut lsulfamyl aniline \)lidincs 2-chliiro-5-nitroaniline 5-nitroQ-toluidine on|- or p-nitroanilinc Z-chloro-4-nitroaniline Z-bromo-Amitnianilinc 2-c \nno-4-nitroanilinc ZA-dinilroanilinc oor -eyanoanilinc 2,-1-d' anoanilinc LS-dic anoanilinc Z-chloro-4-c anoanilinc l4-tllchlurotil1ilinc 3.4-dibromrianilinc oaminoben/otril'luoride 2-amino-5chlonahen/otri d-anlinwlchlonipropiiin lintro -l;llli\llllflc anilide F -chloro-l alimcthylsuliimry linilrw lanisidine aniline 4 chloroJ-anisidinc Z'mtro-4-oct loxyaniline Table 1 -Continued 5-hromi i- 2 -anisidinc Z-metho '5-toluidinc 4-ainino-J-chlorobenzotril'luoridc hut l anthranilatc methyl 4-chloroanthranilate p-:uniniracetophcnonc p-oct lsullonylaniline puminobcnzoic acid. hutyL amide lumino-3.5-dinitrohenzoic acid. hutyl ester lfi-dic ano-4-nitroanilinc Z-amino-S-nitn bcno7ic acid.

prop)! ester -l-aminw" -nitrobcnloic acid.

dieth amine Salimi-Z-anisidine Iamino--l-nitroben7uic acid.

dimctln lamidc 2-nitro-4toluidinc 4-nitro-Z-toluidinc J-chlr )rU-4-C) anoanilinc -l-bro|no lh-dinitriianiline 4-chliiro-2.o-dinitmanilinc 5 L'hl4 iroe ano4-nitroaniline phcn \l anthranilale 2'bromo-4b-dinitroaniline 2-chloro-4.h-dinitroaniline 2-cyano4.hdinilroanilinc Z-bl'tII'I1U h-C}HI'IO-4'LlinlI'U- aniline LaminoJ.S-dinitrohen/otrifluoridc 2.5-dichloro-4-nitroaniline 2.4-dinitro4v-amylsullim laniline p-aminobemophenone p-aminobcnzanilidc 4 aniino-fi-bromobciwophcnone metanilic acid. N-ethyl anilide 4'-amino-3-ehlorol1enlanilidc p-aminoben/oic acid. N-

mcthylanilidc pphcnoxyaniline ZJ-dimcthox --l-phcn lsull'on l aniline 2.;unino-45-dichlorrihcn/ophenolic Z-chloro-hheio lsulforn laniline Laminii-J.S-dinitrobenmic acid. phcn) I ester 1.4-liniil't$-(\-Phl |'l} lsull'oin l aniline p-phcmlsulthnylainilinc l-uninoJfi dinitrohcn/ir phenomaniline crcsidinc oor m-toluidinc n or m'cth hmilinc oor m-anisidinc o-phenctidinc lfi-lidine -dicth l;inilinc 2.5-din1ctho\ anil inc 2.5-diclhoxy aniline o' or m-chloroanilme 5 Cl l0flbZ-illllSltlllll: 5chloro l-tolu idine unaphthylamine TABLE 3 aniline 2 5-\ylidini: ln-toluidinc cresidini:

m-chli iroanilinc nrphcn lencdiaminc Tl-amimiacetanilide 3-aminwvzilcriiliilitlc T-aminocyck ihcxanccarbtwanilidc 5-chloroZ-tirluidinc S-ehloro ..-anisidinc S-ucctalnido-Z-loludilie 5-bcnloamido-Z-anisidinc o-naphthylamine ZA-diaminotolucnc TABLE 4 acct \l chloride mcthoxyaccQl chloride propioinl chloride hiit \r \l chloride valeryl chloridc pclargonyl chloride hc\ahydrohcn/o}l chlr )TiLlL bcn/o \l chloride o-. mor ptoluoyl chloride anisoyl chloride o-. ni or p-chlorohenloyl chloride o-. In or p-hromobeivo \l chloride phcnylacct chloride The following description is representative of the aforementioned prior art procedures.

The first amine can be diazotized by adding sodium nitrite to a solution or suspension of the amine in aqueous hydrochloric or sulfuric acid at a suitable temperature. generally ()25C. it is sometimes advantageous,

for example. in the case of amines having limited solubility in aqueous mineral acid. to replace some or all of the water with an organic solvent. such as acetic acid or a mixture of acetic and propionic acids. Other amines. for example. those containing two or more strongly electron-withdrawing substituents. can be diazotized in nitrosylsulfuric acid. In coupling the diazotized amine to the second aromatic amine. the latter can be dissolved or suspended in dilute aqueous min eral acid. optionally containing an organic solvent such as acetic acid or methanol. and admixed with. by adding thereto or by adding to it. the diazotized amine. The coupling reaction may be accelerated by raising the pH to about 23 with a suitable salt. such as sodium formate or acetate. When the reaction is complete. the pH is raised with a salt or base, such as sodium acetate or sodium hydroxide. to precipitate the monoazo amine in the free base form. The product is isolated by filtration. The monoazo amine can be diazotized in aqueous mineral acid. preferably containing an organic solvent such as acetic acid. with sodium nitrite at lt)3()(. (oupling of the diazonium salt to the third aromatic amine in a suitable solvent such as aqueous mineral acid or an aqueous organic medium. optionally containing mineral acid. produced a disazo amine which is isolated by filtration. As an alternative procedure. the monoazo amine can be diazotized and coupled in situ without a prior isolation step if the reaction medium is chosen with care. Usually. this requires the use of a suitable quantity of an organic solvent. such as acetic acid. The disazo amine is acylated with an acid chloride in the presence of an organic or inorganic acid acceptor. such as pyridine or potassium carbonate. in a suitable or ganic solvent to yield the desired disazo dye.

The dyes of this invention can be applied to water swellable cellulosic materials or to mixtures or blends thereof with synthetic materials. such as polyesters. by the above-described Blackwell et al. process. The cellulosic materials which can be dyed include all forms of cellulose which increase in size and in flexibility upon exposure to water. Suitable materials include natural fibers and purified wood pulps as well as reconstituted cellulose in fiber and film form. Cotton fibers can be dyed in any of the forms in which they are conventionally used in textile materials and after any of the treatments conventionally used to prepare them for dyeing Also included is cotton which has been treated in any way which does not significantly reduce its swelling upon heating with water; raw or scoured cotton and cotton which has been mercerized or otherwise preshrunk are dyeable with the dyes of this invention. Reconstituted ccllulosic fibers which are sufficiently open in structure so that they are swollen by water and penetrated by a dye solvent are dyeable. for example. cuprammonium rayon. Xanthatc viscose rayon normally has a structure which is more difficult to swell and may require exposure to dye. water. and dye solvent for somewhat longer times at lower temperatures. Dyeing of viscose rayon fabric is promoted by pretreatment with ltlYl aqueous caustic. or by the presence of wet ting agents. preferably of the nonionic type. which as sist penetration of the fibers by the dye solvent. Mixtures of cotton and rayon fibers acan be dyed. and the present dyes also can be used to dye purified wood pul and paper. Excluded herein as the water swellable ccllulosic material is cellulose acetate which does not ex hibit the requisite swellability in the presence of water.

The dyes of this invention are particularly useful for dyeing blends of cotton and polyester. such as those containing SUJflY/r polyethylene terephthalate and 2U5(l/I cotton. Since the dyes of this invention can be used to dye both components in a blend. scourability as a factor in dye selection is avoided because of minimization of the problem of cross-staining that is generally encountered when polyester/cellulosic blend fabrics are dyed conventionally with two classes of dyes. such as disperse/vat or disperse/direct dye combinations.

The dyes of this invention dye the substrate directly, that is. they do not require oxidation. reduction, hydrolysis. or any other chemical modification for development of color or fastness. The dyes are yellowbrown to red-brown in shade and exhibit good to excellent fastncss to light. crocking. washing. sublimation and dryclcaning. They are particularly useful for producing mixed shades which are difficult to formulate with a combination of primary (yellow. red and blue) colors.

In dyeing cellulosic materials with the dyes of this in vention using the Blackwell et al. process. water. dye. and dye solvent can be applied to the substrate in any sequence as long as water and dye solvent are simultaneously present at some stage which is either before or simultaneous with actual dyeing. The preferred method for dyeing fabrics composed of cellulosic fibers or mixtures of cellulosic and synthetic fibers to impregnate the fabric with a mixture of one or more dyes. water. and dye solvent in a conventional dye padbath followed by squeezing to remove excess dye liquor. or to print with a solvent-containing printing paste. and subsequently heating to evaporate sufficient water to effect dissolution of the dye. at which time the fabric is dyed. Alternatively. water is evaporated. but in an insufficient amount to effect dissolution of the dye. after which pressure and heat are applied to effect dissolution without further evaporation of water. Dye pastes can be prepared by conventional techniques. such as by milling the dye in the presence of a dispersing agent or surfactant. A dyebath can be prepared by diluting the dye paste with water or with aqueous solvent. Addition of a solvent to the dye paste before addition of water may cause dye separation and usually is avoided. lt will be understood by those skilled in the art that additives other than a dye solvent and a dispersing agent can be present in dyebaths. Such additives frequently include migration inhibitors. such as purified vegetable gums. and wetting agents. examples of which are ionic and nonionic surfactants. such as ethylene oxide condensation products. hydrocarbon sulfonates and long-chain alcohol sulfates. Dyebaths used in practicing this invention also can contain dyes other than those of this invcntion; for example. direct dyes or fiber reactive dyes can be present for shading purposes.

In the preferred dyeing procedure with the dyes of this invention. an aqueous dye dispersion and the or ganic solvent are applied to the fabric from a single padbath. The amount of water in the padbath usually is 7(l95 weight 7: and the solvent. 5-30 weight 7:. The padded fabric is heated at l 8()-225C. for 30-180 seconds. For cotton. temperatures as low as l 50C. usually are adequate. The dyed fabric generally is given an aqueous scour. or an aqueous scour followed by a perchlorocthylcnc scour. to ensure complete removal of surface dyc.

The following experiments show the utility of the dyes of this invention.

Dyeing 65/35 Dacron'- Polyester/Cotton Blend Fabrics A. A padbath was prepared from:

50 grams 100 grams to I liter.

A continuous length of 65/35 Dacron polyester/cotton fabric was padded at 607? uptake, based on the weight of the fiber. and the padded fabric was passed at a rate of 2 yards per minute between two 1,000 watt infrared lamps (Fostoria-Fannon. lncv Infrared Heater Model 6,624 with each lamp shining on opposite surfaces of the fabric from a distance of about 3 inches. The continuously moving fabric was passed through a circulating air oven at 80l00C.. with a hold-up time of one minute, and then through an oven at 2002 C. with a hold-up time of 1.7 minutes. The hot dry fabric was cooled to room temperature and rinsed for one minute each in sequence: in water at 30C.. in water at 90-95C.. at 9095"Cv in water containing l7r of an ether-alcohol sulfate detergent. in water at MP-95C.. and in water at 2030C. The material was then dried and scoured for five minutes in perchloroethylene at 50C. A unifomily deep yellow-brown shade of excel lent fastness to light. crocking. sublimation. washing and dryclcaning was obtained.

B. Experiment A was repeated except that the dye of Example 2 was employed. The polyester/cotton blend fabric was uniformly dyed a deep redbrown shade of excellent fastness properties.

an aqueous paste l5: actiyc ingredient) containing the dye of izxamplc 3 l0 grams purified natural gum ether thickener 0 grams vtater grams.

The printed fabric was heated at 200C. for 100 seconds, scoured in water containing an ether-alcohol sulfate detergent at about 90C. for 5 minutes and dried. The printed areas were strongly dyed in a yellow-brown shade.

Dyeing of Dacron Polyester The dyes of this invention can be applied to polyester from an aqueous dyebath under pressure or by a padheat procedure to yield similar shades. The following experiment shows the amenability of these dyes to the Thermosol process.

D. Dacron polyester fabric was immersed for fiftccn minutes at 82C. in an aqueous bath containing 1'7; ether-alcohol sulfate surface active agent and i9? tetra- ZU grants 1 sodium pyrophosphate. The fabric was rinsed in cold water. dried. then padded at 50-60% pickup. based on the dry fabric weight. in a dyebath containing:

an aqueous dye paste 1 15% active ingredient] containing the dye of Fsample l 50 grams purified natural gum thickener Z0 grants water to 1 liter.

The padded material was passed through an infrared predryer, then heated to and held at 213C. for seconds. The fabric was rinsed in water at 27C.. scoured for 5 minutes at 93C. in water containing l% etheralcohol sulfate detergent. rinsed in water at 27C. and dried. The polyester fabric was dyed a deep dull orange shade.

The following examples are given to illustrate the in vention. All parts are given by weight.

EXAMPLE 1 SN-Sodium nitrite (144 parts) was added to a mixture of 76 parts of 3-chloro-2toluidine. 900 parts of acetic acid, 300 parts of water and 128 parts of concentrated hydrochoric acid which had been cooled to 0C. After the reaction mixture had been stirred at 0l0C. for 30 minutes. excess nitrite was destroyed with sulfamic acid and a solution of 53 parts of 2.5-xylidine in parts of acetic acid was added. The mixture was stirred for two hours. after which the solids were isolated by filtration. washed with water and dried. The yellow. monoazo intermediate (98.5 parts) was chromatographically pure. A mixture containing 10 parts of the intermediate. parts of acetic acid. 50 parts of water and 22.4 parts of concentrated hydrochloric acid was cooled to 0C. and treated with 9.76 parts of 5N- sodium nitrite solution. The reaction mixture was stirred for 30 minutes. after which excess nitrite was destroyed with sulfamic acid and the diazo solution was clarified by filtration. The filtrate was cooled externally to 05C. and treated with a solution of 7.7 parts of 3 aminobenzanilide in 50 parts of acetic acid. The mixture was stirred for 30 minutes and the pH was then adjusted to 2.7 with 30% caustic soda. Stirring was continued for another 3 hours. after which the solids were isolated by filtration. washed with water and dried. Thin Layer Chromatography (TLC) indicated that the brown disazo intermediate thus formed contained only trace amounts of two yellow impurities. A solution of 15 parts of the disazo intermediate in 100 parts of pyridine was treated with l8 parts of benzoyl chloride and the reaction mixture was stirred at 8090C. for 3 hours. TLC showed that complete conversion of the brown intermediate to the orange product had occurred. The mass was drowned in 2.000 parts of water and the solids were isolated by filtration. washed with water and dried. The dye was purified by slurrying in hot ethanol. after which the solids were isolated by filtration and dried. The chromatographically pure dye melted at 204207C.. showed a maximum absorptiw ity (a,,,., in dimcthylformamide (DMF) of53.0 liters/- gram/cm. (lg. "cm. l at a wavelength ()t,,,., of420 mu. and had the structure CH CH NHCOC H5 N=N NHCOC H EXAMPLE 2 SN-Sodium nitrite (24.4 parts) was added to a stirred mixture of 14.1 parts of 3-chloro-2-toluidine. 200 parts of acetic acid. 50 parts of water and 28 parts ofconcentrated hydrochloric acid which had been cooled to C. After 30 minutes excess nitrite was destroyed with sulfamic acid. A solution of 4.3 parts of a-naphthylaminc in 25 parts of DMF was then added and the reaction mixture was stirred for 2 hours. The solids were isolated by filtration and washed with 5094 aqueous acetic acid and then with water. The crude intermediate (2) parts] was slurried in SN-hydrochloric acid to remove a red impurity. then isolated by filtration and washed thoroughly with water. The wet cake was added to a mixture of 300 parts of acetic acid. 60 parts of propionic acid and l l.2 parts of concentrated hydrochloric acid. The mixture was cooled externally to 0C. and di azotization was effected by adding 34.4 parts of 5N- sodium nitrite. The mixture was stirred for 90 minutes. after which excess nitrite was destroyed with sulfamic acid. The charge was clarified by filtration and a solution of parts of 3'-aminobenzanilide in I00 parts of acetic acid was added thereto. After stirring for 1 hour. the pH was raised by adding 20 parts of sodium hydroxide solution and stirring was continued for l hour. The solids were isolated by filtration. washed with 50W acetic acid. then with water and dried, yiclding 2% parts of the disazo intermediate. A mixture of IS parts of the intermediate. 100 parts of pyridine and 18 parts of bcnzoyl chloride was heated at 70-R0(. for two hours. lhe mass was cooled and drowned in 2.000 parts of water. The produce was isolated by filtration, washed with water and dried. affording 16 parts of crude dye. It was slurried in hot ethanol. isolated by filtration and dried. The ehromatographically pure dye melted at 2-lh-249C and had an a,,,, in DMF of42.7 lg. cm. at a of 490 mu; it had the structure EXAMPLE 3 A mixture of 6) parts of p-nitroaniline. 800 parts of acetic acid. 200 parts of propionic acid and 148 parts of 98% sulfuric acid was cooled to 0C. and diazotization was effected by the rapid addition of 345 parts of solid sodium nitrite. After stirring for 30 minutes excess nitrite was destroyed with sulfamic acid and the diazo preparation was clarified by filtration. The filtrate was cooled to 0C. and 53.6 parts of m-toluidine were added. The charge was stirred overnight. Another parts of acetic acid were added. the slurry was cooled to 0C. and then 35 parts of solid sodium nitrite were added. After the reaction mixture had been stirred for 1 hour. excess nitrite was destroyed with sulfamic acid and a solution of 71.5 parts of a-naphthylamine in 200 parts of acetic acid was added. The reaction mixture was stirred overnight and the solids (dis azo intermediate) were isolated by filtration. washed with acetic acid and slurried in [.000 parts of I0 hydrochloric acid. The solids were again isolated by filtration. washed with water until acid free and dried. A mixture of 20 parts of the disazo intermediate and 150 parts of pyridine was slowly treated with 30 parts of acetyl chloride. After stirring for 30 minutes. the reaction mixture was drowned in ice water and the solids were isolated by filtration. washed with water and dried. The crude dye was reslurried successively in ethanol and in aqueous DMF and then recrystallizied from DMF. The chromatographic-ally pure dye melted at 273275C. and had an a,,,,, in DMF of 60 l.g.' cm. at a A of 435 mu. The visible spectrum exhibited a second peak at 370 my (a,,,,, 50 |.g."cm. The dye product had the structure N'HCOCH EXAMPLES 4-34 TABLE 5 Shade On 6513 5 l)acron" {Poly cstcn( 'otton Arnax.

l lHl/Jl NHUUR H it H fl J-NO l.4naphthylene phenyl phcnyl phcnyl l" nitro phenyl phcnyl phenyl phenyl phcny l phenyl phcnyl Ll-Ui lib-Eh] 350 535 mu 4.10 34o red-brown red-bro a yellow brow n red-brow n ycl lou brou ycllow l roun Ulllngclun n red hn m n red-brow n 

1. DYE OF THE FORMULA
 2. Dye of the formula 